The present invention is directed to a method of and an apparatus for detecting and counting articles that are within a predetermined size range into lots having a specific number of articles. The lots are collected in at least one bin having at least a first outlet gate and a second outlet gate. A control unit causes a first outlet gate to open when the count of articles having the predetermined size is equal to the predetermined number. A detector unit generates an out-of-size signal when an article falls outside of the predetermined size range. In response to the out-of-size signal, the control unit causes a second outlet gate to open, thereby rejecting the articles in the at least one bin. In addition, the methods and apparatus of the present invention may detect and count articles having a predetermined color into lots having a specific number of colored articles. For convenience, the following discussion will be directed only to counting articles having a predetermined size.
Devices for counting or aggregating articles are known. For example, U.S. Pat. No. 5,454,016, which is incorporated herein by reference in its entirety, discloses a method and apparatus for counting irregularly shaped articles. A pair of alternately energized light sources is provided at a sensing plane through which articles to be counted pass. Each of the light sources emits a light beam that is at an angle to the other light beam, such as an angle of about 90xc2x0.
U.S. Pat. No. 5,804,772, which is incorporated herein by reference in its entirety, discloses an apparatus and method for aggregating a desired number of articles without individually counting out each article to achieve the desired number. A stream of the articles is discharged into a weigh hopper until.substantially a predetermined weight of articles is in the hopper. The number of articles in the hopper is determined from the total weight of the hopper and the weight of a single article.
However, known devices do not detect and package a lot of articles having a predetermined count and a predetermined size and reject lots having articles falling outside the predetermined size range.
It is an object of the present invention to overcome the deficiencies of the known devices and methods and to provide an apparatus and method for detecting and counting articles that accurately counts a predetermined number of discrete articles that are within a predetermined size range.
It is another object of the present invention to provide an article.detecting and counting apparatus that is relatively simple and inexpensive to manufacture and to maintain and that is both accurate and reliable.
In accordance with one aspect of the present invention, a counter unit for counting discrete articles within a predetermined size range into lots having a predetermined number of articles includes (1) a first conveyor that delivers a flow of articles separated at intervals, and (2) at least one bin positioned to receive articles from the conveyor. The at least one bin may have first and second outlet gates for emptying the articles into first and second separate locations. A detector unit counts the articles that are received from the conveyor into the at least one bin and which fall within the predetermined size range. A control unit causes the first outlet gate to open when the count of articles is equal to the predetermined number of articles. However, when an article falls outside the predetermined size range, the detector generates an out-of-size signal. The control unit, upon receipt of the out-of-size signal from the detector unit, causes the second outlet gate to open, thereby rejecting the articles. The counter unit may also be used to for counting articles having a predetermined color into lots having a predetermined number of articles. When an article does not have the redetermined color, the detector generates an out-of-color signal. The control unit, upon receipt of the out-of-color signal from the detector unit, causes the second outlet gate to open thereby rejecting the articles.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.